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CP04 notice: what it means and what to do
Got an IRS CP04 notice? Here is what it means, your deadline, what to check before you answer, and how to reply. Check your own letter free: it stays on your phone.
Check my CP04 notice freeWhat the IRS says this notice is about
Your tax return shows that you or your spouse served in a combat zone, a qualified contingency operation, or were in a hazardous duty station during the tax year shown on your notice. As a result, you may be eligible for tax deferment.
What you need to do
Use the Document Upload Tool and the access code provided on your notice to complete and submit Form 15109, Request for Tax Deferment PDF , along with supporting documents by the due date on your notice.
If you can’t use the Document Upload Tool :
- Download and complete Form 15109 PDF . Follow the instructions on the form to request tax deferment and fax your documents to the number provided on Form 15109; or
- Mail your documents to the address at the top of your notice.
Your deadline
Answer by the date printed on your notice. If there is no date, answer as soon as you can, and call the number on the notice if you need more time.
What to check before you answer
Send the documents the IRS asks for
Make copies, number the pages, and send them so they arrive by the date on your letter. If you need more time, call before the date and ask for it.
Is this letter really from the IRS?
The IRS writes first by mail. A real letter shows a notice or letter number, your name and part of your tax ID number. The IRS does not ask for payment by gift card, crypto or wire transfer. If in doubt, sign in to your IRS online account, where many notices are listed.
You may want to
- Review Publication 3, Armed Forces’ Tax Guide
- Review this notice with your tax preparer.
What happens if you don’t respond
If we don't receive your completed Form 15109 by the due date shown on your notice you won’t receive tax deferment benefits.
If you don’t file your return on time and pay taxes due, you may be subject to collection action for taxes, interest, and/or penalties that you owe.
Common questions
What deferments are available to those who serve in a combat zone? (updated April 18, 2025)
You could be eligible for an extension for filing tax returns, paying taxes, filing claims for refund, and taking other actions with the IRS.
If you currently serve or work in support of the armed forces outside of the United States and Puerto Rico, you could receive an automatic extension.
For more information about an extension, review Publication 3, Armed Forces’ Tax Guide .
If it's an automatic extension, why do I need to provide the requested information? (updated April 18, 2025)
We need to verify that you’re eligible to receive the automatic extension. We need the dates that you served or worked in a qualified area so we can update your account.
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